An electronic system that includes multiple sub-systems (electronic circuitry blocks (ECBs) herein) may have varying power requirements that differ for each sub-system. Each ECB may include one or more of a processor core or portion thereof, graphics processing unit, system unit agent, memory controller unit, display engine unit, cache controller unit, memory bank such as static random access memory (SRAM) block, audio engine, modem unit, wireless connectivity unit (e.g., wifi), controller (e.g., debug controller, peripheral component interconnect express (PCie) controller, local area network (LAN) controller, universal serial bus (USB) controller, serial advanced technology attachment (SATA) controller), etc.), on-chip connectivity fabric, etc. Typically, each ECB receives power via a distinct source such as a voltage regulator (VR). Each source may have a current rating that is typically chosen to be a worst case current value for the sub-system that it supplies, e.g., a highest current value that the corresponding sub-system may consume in a highest power usage scenario.
However, only very rarely does an ECB reach its worst case power scenario. Further, not all ECBs reach worst case concurrently. Hence, specification that each VR have a worst case current rating to supply power to its respective ECB may result in overcapacity for a large portion of run time of the system, which can be both costly and wasteful of resource capability and can result in reduction in system performance.